The proposed project will examine the role of maternal, environmental and infant factors (e.g., social support, infant temperament) which combine with maternal depression to place infants at risk for problems in social- emotional functioning. I am proposing to screen 600 women for depression in the second trimester of pregnancy in order to ascertain 60 clinically depressed mothers and 60 nondepressed mothers. Mothers who meet criteria for DSM-III-R major depression on the screening instrument and a matched sample of mothers with very few depressive symptoms will be administered a structured psychiatric interview at two months post partum. Mothers who meet DSM-III-R criteria for major depression based on the interview information and those who have no history of depression will be followed with their infants in a short-term longitudinal study. Mother-infant pairs will be evaluated at 4 and 14 months post partum. I anticipate a final sample of at least 50 depressed and 50 nondepressed mother-infant dyads at the 14 month follow-up. The specific aims of the study are: 1) to compare depressed and nondepressed mothers with respect to: a) social supports; and b) dimensions of parenting; 2) to compare infants of depressed and nondepressed mothers with respect to: a) affective displays; b) social responsivity; c) temperament; and d) attachment patterns; 3) to address individual differences within depressed mothers by examining whether maternal characteristics such as concomitant psychopathology, severity of global psychopathology, social supports, and parenting styles differentially predict infant security of attachment at 14 months postpartum; and 4) to examine maternal factors in pregnancy and at 4 months postpartum in combination with measures of infant temperament at 4 months to predict infant security of attachment and maternal sensitivity at 14 months postpartum. A unique aspect of the proposed study is the careful characterization of the infant in terms of behaviors which are hypothesized to influence the infant's ability to participate in a reciprocal interaction with their caregiver (e.g., emotional reactivity, sociability). While treatments are currently available which will potentially remediate the symptoms of maternal depression, more data are required to develop prevention strategies which will minimize risk to offspring of depressed mothers. Identifying those depressed mothers who are at greatest risk for difficulties in parenting and those infants who are at greatest risk for problems in affect regulation should inform the development of specific preventive interventions.